t=(i for i in range(1,4))
print(t)
# t=tuple(t)
# print(t)
# #遍历
# for item in t:
#     print(item)
print(t.__next__())
print(t.__next__())
print(t.__next__())

# 此时再去将t转换为元组并输出，发现无元素，因为元素都被取出了
t=tuple(t)
print(t)